<template>
  <div class="component-upload-image">
    <el-upload
      ref="imageUpload"
      multiple
      :action="uploadImgUrl"
      list-type="picture-card"
      :on-success="handleUploadSuccess"
      :before-upload="handleBeforeUpload"
      :limit="limit"
      :on-error="handleUploadError"
      :on-exceed="handleExceed"
      :before-remove="handleDelete"
      :show-file-list="true"
      :headers="headers"
      :file-list="fileList"
      :on-preview="handlePictureCardPreview"
      :class="{ hide: fileList.length >= limit }"
    >
      <el-icon class="avatar-uploader-icon"><plus /></el-icon>
    </el-upload>
    <!-- 上传提示 -->
    <div v-if="showTip" class="el-upload__tip">
      请上传
      <template v-if="fileSize">
        大小不超过 <b style="color: #f56c6c">{{ fileSize }}MB</b>
      </template>
      <template v-if="fileType">
        格式为 <b style="color: #f56c6c">{{ fileType.join("/") }}</b>
      </template>
      的文件
    </div>

    <el-dialog
      v-model="dialogVisible"
      title="预览"
      width="800px"
      append-to-body
    >
      <img
        :src="dialogImageUrl"
        style="display: block; max-width: 100%; margin: 0 auto"
      >
    </el-dialog>
  </div>
</template>

<script setup>
import { getToken } from '@/utils/auth';

const props = defineProps({
	modelValue: [String, Object, Array],
	// 图片数量限制
	limit: {
		type: Number,
		default: 5,
	},
	// 大小限制(MB)
	fileSize: {
		type: Number,
		default: 5,
	},
	// 文件类型, 例如['png', 'jpg', 'jpeg']
	fileType: {
		type: Array,
		default: () => ['png', 'jpg', 'jpeg'],
	},
	// 是否显示提示
	isShowTip: {
		type: Boolean,
		default: true
	},
});

const { proxy } = getCurrentInstance();
const emit = defineEmits();
const number = ref(0);
const uploadList = ref([]);
const dialogImageUrl = ref('');
const dialogVisible = ref(false);
const baseUrl = import.meta.env.VITE_APP_BASE_API;
const uploadImgUrl = ref(import.meta.env.VITE_APP_BASE_API + '/common/upload'); // 上传的图片服务器地址
const headers = ref({ Authorization: 'Bearer ' + getToken() });
const fileList = ref([]);
const showTip = computed(
	() => props.isShowTip && (props.fileType || props.fileSize)
);

watch(() => props.modelValue, val => {
	if (val) {
		// 首先将值转为数组
		const list = Array.isArray(val) ? val : props.modelValue.split(',');
		// 然后将数组转为对象数组
		fileList.value = list.map(item => {
			if (typeof item === 'string') {
				if (item.indexOf(baseUrl) === -1) {
					// eslint-disable-next-line no-param-reassign
					item = { name: baseUrl + item, url: baseUrl + item };
				} else {
					// eslint-disable-next-line no-param-reassign
					item = { name: item, url: item };
				}
			}
			return item;
		});
	} else {
		fileList.value = [];
		return [];
	}
},{ deep: true, immediate: true });

// 上传前loading加载
function handleBeforeUpload(file) {
	let isImg = false;
	if (props.fileType.length) {
		let fileExtension = '';
		if (file.name.lastIndexOf('.') > -1) {
			fileExtension = file.name.slice(file.name.lastIndexOf('.') + 1);
		}
		isImg = props.fileType.some(type => {
			if (file.type.indexOf(type) > -1) return true;
			if (fileExtension && fileExtension.indexOf(type) > -1) return true;
			return false;
		});
	} else {
		isImg = file.type.indexOf('image') > -1;
	}
	if (!isImg) {
		proxy.$modal.msgError(
			`文件格式不正确, 请上传${props.fileType.join('/')}图片格式文件!`
		);
		return false;
	}
	if (props.fileSize) {
		const isLt = file.size / 1024 / 1024 < props.fileSize;
		if (!isLt) {
			proxy.$modal.msgError(`上传头像图片大小不能超过 ${props.fileSize} MB!`);
			return false;
		}
	}
	proxy.$modal.loading('正在上传图片，请稍候...');
	number.value ++;
}

// 文件个数超出
function handleExceed() {
	proxy.$modal.msgError(`上传文件数量不能超过 ${props.limit} 个!`);
}

// 上传成功回调
function handleUploadSuccess(res, file) {
	if (res.code === 200) {
		uploadList.value.push({ name: res.fileName, url: res.fileName });
		uploadedSuccessfully();
	} else {
		number.value--;
		proxy.$modal.closeLoading();
		proxy.$modal.msgError(res.msg);
		proxy.$refs.imageUpload.handleRemove(file);
		uploadedSuccessfully();
	}
}

// 删除图片
function handleDelete(file) {
	const findex = fileList.value.map(f => f.name).indexOf(file.name);
	if (findex > -1 && uploadList.value.length === number.value) {
		fileList.value.splice(findex, 1);
		emit('update:modelValue', listToString(fileList.value));
		return false;
	}
}

// 上传结束处理
function uploadedSuccessfully() {
	if (number.value > 0 && uploadList.value.length === number.value) {
		fileList.value = fileList.value.filter(f => f.url !== undefined).concat(uploadList.value);
		uploadList.value = [];
		number.value = 0;
		emit('update:modelValue', listToString(fileList.value));
		proxy.$modal.closeLoading();
	}
}

// 上传失败
function handleUploadError() {
	proxy.$modal.msgError('上传图片失败');
	proxy.$modal.closeLoading();
}

// 预览
function handlePictureCardPreview(file) {
	dialogImageUrl.value = file.url;
	dialogVisible.value = true;
}

// 对象转成指定字符串分隔
function listToString(list, separator) {
	let strs = '';
	// eslint-disable-next-line no-param-reassign
	separator = separator || ',';
	for (const i in list) {
		if (undefined !== list[i].url && list[i].url.indexOf('blob:') !== 0) {
			strs += list[i].url.replace(baseUrl, '') + separator;
		}
	}
	return strs != '' ? strs.substr(0, strs.length - 1) : '';
}
</script>

<style scoped lang="scss">
// .el-upload--picture-card 控制加号部分
:deep(.hide .el-upload--picture-card) {
    display: none;
}
</style>